Holding devices for centering magnets of cathode ray tubes



Juli-:21, .1970 KATSUYOSHI SUGIURA 1,

HOLDING DEVICES FOR CENTERING MAGNETS CATHODE RAY TUBES Filed April 5, 1968 INVENTOR KAT5 UYasm SUGIURA ATTORNEY United States Patent U.S. Cl. 335212 8 Claims ABSTRACT OF THE DISCLOSURE -A holding device for a centering magnet of a cathode ray tube located on the periphery of a mounting member adapted to receive the neck of the cathode ray tube and in parallel with a supporting plate, a letter C shaped clip of a resilient and flexible material is inserted through an opening in the mounting member to clamp the centering magnet.

BACKGROUND OF THE INVENTION This invention relates to a cathode ray tube and more particularly to a holding device of a centering magnet utilized for adjusting the position of an electron beam of a cathode ray tube.

Generally the centering magnet is held in position by the cooperation of a cylindrical clamping member mounted to surround the neck portion of the cathode ray tube and a flange like member extending from said clamping member, for example, a rear lid of a vessel containing a deflection coil and functions to adjust the position of the electron beam emitted by the cathode ray tube.

' According to a prior construction such a centering magnet is, held by projections on the outer periphery of the clamping member and said rear lid. However, when the clamping memberfis clamped'to the neck portion of the cathoderay tube by means of a clamping band, the clamping member becomes deformed thus causing unstable the holding action forthe centering magnet provided by theprojections" on the clamping member. In some case,

thisa'will'result in a uneven rotary torqueofthe centering magnet, thusaifecting the adjustment of the deflection of the electron beam.

OF INVENTION .Itis anobject ofthis invention to provide an improved holding device for a centering magnet of a cathode ray tube which will not affect the state of mounting of the centering magnet even whenthe clamping member is deformed by the'clamping force of the clamping band, I

"Another object of this invention is'to provide a: simple and inexpensive holding device fora centering" magnet of a cathode ray tube. H

A further object "ofthis invention is to-provide a holding device which can readily mount the centering magnet.

Still further object of this invention is to provide a novel clip for holding the centering magnet.

According to a preferred embodiment of this invention, the holding device for a centering magnet of a cathode ray tube comprises a clip, a mounting plate, a mounting member extending from the mounting plate, said mounting member being used to receive and hold the neck of the cathode ray tube, and a centering magnet concentrically disposed on the outer periphery of the clamping member and extending in parallel with the mounting plate.

The clip is in the form of a letter C configuration with projections on the opposite ends and is made of a resilient and flexible material. The clip is inserted through a slot or a perforation in the mounting member to the operating 3,521,206 Patented July 21, 1970 position at which it clamps the centering magnet between its ends.

BRIEF DESCRIPTION OF THE DRAWING These and other objects together with advantages and features of this invention will become apparent and this invention will be better understood from the following description, reference being made to the accompanying drawing, in which:

FIG. 1 is a plan view of a holding device for a centering magnet of a cathode ray tube embodying this invention;

FIG. 2 is a sectional view taken along a line II-II, in FIG. 1;

FIG. 3 is a perspective view of one example of the novel clip;

FIG. 4A is a partial view, partly in section, to explain the method of mounting the clip shown in FIG. 3;

FIG. 4B is a partial view, partly in section, illustrating the holding state of the holding device embodying this invention;

FIG. 5 is a partial view, partly in section, of a modified embodiment of this invention;

FIG. 6 is a perspective view of a modified clip embodying this invention, and

FIG. 7 is a partial view, partly in section, to explain the method of mounting the clip shown in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIGS. 1 and 2 of the accompanying drawing, there is shown a mounting plate 10 which cornprises 'a vertical wall of a non-magnetic rear lid of a vessel containing a deflection coil, not shown, of a cathode ray tube. A cylindrical clamping member 11 integrally formed with the mounting plate 10 is provided to extend longitudinally of the neck (no-t shown) of the cathode ray tube from an opening 12 adapted to receive said neck. The clamping member 11 is also made of a non-magnetic material and is provided with a plurality of tongues 14 separated by longitudinally extending slots 13. The construction of the clamping member thus far described.

or radial portion of the mounting plate 10 vare held. in.

position by a plurality of letter C shaped clips 18. Each one of the clips 18 is received in one of the slots 13' of the clamping member 11 with its upper end abutted against the upper surface of the magnet 15 and with its lower end against the lower surface of the magnet 16,

thus clamping magnets 15 and 16, said lower end extend-. ing through a perforation 17 through the mounting plate l0.-The, centering magnets 15 and 16 are adjustably rotated by means of handles 151 and 161'.

FIG. 3 shows the detail of the construction of the letter C shaped clip 18. The clip 18 is made of a resilient and flexible material and comprises a main body 181 and two arms 182 and 183 extending from the opposite ends of the main body 181. These arms 182 and 183 are provided with opposing projections 184 and 185 at their free ends, said projections having a wedge shaped cross section with inclined surfaces 186 and 187, the purpose thereof will be described later.

The method of holding the centering magnets with said letter C shaped clips will now be described with reference to FIGS. 4A and 4B. As above described the centering magnets and 16 are disposed on the periphery of the cylindrical clamping member 11 in parallel with the mounting plate 10. To hold in position centering magnets 15 and 16 with the C shaped clips, at first each clip is inserted in the opening 12 of the cylindrical clamping member 11, which is adapted to receive the neck of the cathode ray tube, then the arm 182 of the clip 18 is projected outwardly through one of the slots 13 until the tip of the projection 184 comes to engage a point as A on the upper surface 151 of the centering magnet 15 with the inclined surface 187 of the other projection 185 thereof engaged with the inner periphery B of the mounting plate 10. Then the lower portion of the rear surface of the main body 181 of the clip 18 is strongly forced in a direction indicated by an arrow C. As has been pointed out before, as the clip is resilient and flexible, the inclined surface 187 will slide along the inner periphery B of the mounting plate. During this movement, the clip can elongate. Then the tip of the projection 185 will be brought into contact with the lower surface 101 of the mounting plate 10. Further forward movement of the clip 18 causes the tips of the inclined surfaces 186 and 187 thereof to slide along the uppersurface 151 of the centering magnet 15 and the lower surface 101 of the mounting plate 10, respectively. Finally, the projection 185 will be inserted in the perforation 17 through the mounting plate 10, as shownin FIG. 4B. At this time, the clip 18 can restore its original state by its resiliency and flexibility and can positively clamp the centering magnets 15 and 16 between the tips of the projections 184 and 185. Since angles between the inclined surfaces 186 and 187 of the projections and the upper and lower surfaces of centering magnets are acute angles, forward movement of the clip 18 can be made smoothly. As shown in FIGS. 4A and 4B a sliding piece such as a sheet of paper 19 may be interposed between centering magnets 15 and 16 in order to assure their smooth relative rotary movement.

While in the above embodiment the projections 185 of the letter C shaped clip 18 is inserted through perforation 17 of the mounting plate 10 and the projection 185 is formed to project through the perforation 17 this invention is not limited to this particular construction. Alter natively, a recess 20 may be provided on the lower surface of the mounting plate 10 to receive the projection 185 of the clip 18, as shown in FIG. 5. In this case however, the opposite surface of the mounting plate is formed with a corresponding raised portion to rotatably support the lower surface of the centering magnet 16.

FIG. 6 illustrates a modified letter C shaped clip of this invention. This modification is substantially identical to the embodiment shown in FIG. 3 except that it includes a pair of pins 188 and 189 on the opposite sides of the arm 182 of the clip 18. These pins 188 and 189 assure easy mounting of the clip 18.

' Thus, as shown in FIG. 7, the arm 183 of the clip 18 is inserted in the clamping member 11 through one of the slots 13 thereof until pins 188 and 189 are arrested by the tongues 14 on the opposite sides of said slot 13. Thereafter the clip 18 is pushed downwardly along the slot 13 until the tip of the projection comes to engage the upper surface 151 of the centering magnet 15. Then the clip is rotated to the condition shown in FIG. 4A

around a pivotal point defined by the line of contact between pins 188, 189 and tongues 14. Thereafter, the clip is operated in the same manner as has been described in connection with FIGS. 4A and 4B.

Instead of inserting the letter C shaped clip 18 through the slot 13 of the clamping member 11, it may be inserted through any suitable aperture such as a perforation independently provided through the clamping member.

While the invention has been described in terms of preferred embodiments it will be understood that many changes and modifications may be made without departing from the true spirit and scope of the invention as defined in the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A holding device for a centering magnet of a cathode ray tube comprising a clip, a mounting plate, a mounting member extending from said mounting plate, said mounting member being used to receive and hold the neck of said cathode ray tube, and a centering magnet concentrically disposed on the outer periphery of said mounting member and extending in parallel with said mounting plate, said clip being in the form of a letter C configuration with projections on the opposite ends and being made of a resilient and flexible material, said mounting plate being provided with means to engage one end of said clip, and said clip being mounted through said mounting member to clamp said' centering magnet.

2. The holding device according to claim 1 wherein said means to engage one end of said clip is a perforation through said plate.

3. The holding device according to claim 1 wherein said means to engage one end of said clip is a recess to receive said one end of the clip.

4. The holding device according to claim 1 wherein said mounting member is provided with a slot to receive said clip.

5. The holding device according to claim 1 wherein said mounting member is provided with an aperture to receive said clip.

6. The holding device according to claim 1 wherein said mounting plate comprises a rear lid of a vessel for containing the deflection coil of said cathode ray tube.

7. The holding device according to claim 1 wherein said letter C shaped clip comprises a main body, arms extending from the opposite ends of said main body and opposing projections on the free ends of -said arms, said projections having a wedge shaped cross-section with an inclined surface.

8. The holding device according to claim 7 wherein a pair of laterally extending pins are provided on the opposite sides of one of said arms of said letter C shaped clip.

References Cited UNITED STATES PATENTS 2,885,586 5/1959" Mech 313-76 3,136,931 6/ 1964 Harten et al. 316-76XR GEORGE HARRIS, Primary Examiner US. Cl. X.R. 313-76 

